Executor error: Sort exceeded memory limit (find().sort) MongoDB Origin: Data OSI layer 7 · Application Last updated 5 Nov 2026

MongoServerError: Executor error during find command :: caused by :: Sort exceeded memory limit of 104857600 bytes, but did not opt in to external sorting

A find().sort() without a supporting index had to sort too much data in memory.

Exact message you may see Executor error during find command :: caused by :: Sort exceeded memory limit of 104857600 bytes, but did not opt in to external sortingSort operation used more than the maximum 33554432 bytes of RAM. Add an index, or specify a smaller limitOperationFailed: Sort exceeded memory limitQueryExceededMemoryLimitNoDiskUseAllowed find sort
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Seen on: MongoDB

Meaning

Create an index matching the sort (and filter): e.g. { status: 1, createdAt: -1 } for find({status}).sort({createdAt:-1}). Add limit() and projections. allowDiskUse(true) on find (MongoDB 4.4+) works as a stop-gap.

Common causes

  • Sort on an unindexed field
  • Compound index with the wrong key order
  • Large documents sorted fully
  • Missing limit()
  • Filter not using an index

⚡ Quick fix

  1. db.orders.createIndex({ status: 1, createdAt: -1 })
  2. Add .limit(n) and projection
  3. Use .allowDiskUse(true) temporarily

Detailed fix by platform

mongosh

  1. db.orders.find({status:"paid"}).sort({createdAt:-1}).explain("executionStats") shows SORT stage

How to diagnose

  1. explain — SORT stage in memory?
  2. Index — Matches filter+sort?
  3. Limit — Used?

🔧 Still not fixed?

Many errors look alike. If the steps above didn’t solve it, one of these is probably what you’re facing:

Where this error sits

Origin: Data. Errors that are often confused with or caused by this one (click to open):

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